Rainey Reitman of the Electronic Frontier Foundation said that technically, it is indeed all legal, but she emphasized that people don't really understand how their random thoughts, disclosures or opinions on social media may be exploited.

"I think people don't realize when they sign up for these sites that the government is going to be routinely monitoring and sifting through this data," she said.

"If Coca-Cola is reading all my tweets," Dan Zarrella points out, "it's not as scary as if the DOD is reading all my tweets, right?"